Musculoskeletal System | Muscle Mechanics | Twitch, Summation, & Tetanus 

God bless you house, your cow, you car, your wife, your brain and everything that concerns you... you a life saver

Don't mind me. 0:22 muscle fiber types(other videos) 0:38 [Video main topic] Graded muscle responses (2 main types of stimuli) 1:03 Resting membrane potential/Threshold potential(muscle cell) 1:08 Graded Response depends on Frequency and Strength of [Neural Stimuli]-primary(Somatic) stimulus for skeletal muscle fibers 2:05 Muscle Twitch relates to Motor Unit 2:23 Twitch=Rapid muscle contraction(response) from one neural stimulus 3:10 Motor Unit= motor neuron + muscles fibers (sup by motor neuron) 3:47 Recap 4:38 Structure of skeletal muscle 5:15 3 phases of muscle twitch 1)Latent 2)Contraction 3)Relaxation 10:21-contraction(cool) 11:05 Max Voltage-end of contraction(peak?) activates gates, opens channels for potassium ions to leave cell 11:57 (Relaxation) Tension decreases- reverse slide? 12:46 Recap muscle twitch 17:32 Easy on that sodium ion influx, they say the sarcoplasmic reticulum calcium release really stings when it gets in your 👀. Later mania. What up depression.

This is my first comment ever on social media but I had to comment on how great of a teacher you are. We need more teachers like you, who care about the education of others. Your videos have truly helped me in desperate times during my A&P class! THANK YOU!!!

I have met only few people in my long journey with science who can explain like you sir 👍🏽👍🏽 keep going

You are my favorite RU-vid instructor. No one explains things so simply as you do.

Ninja Nerd is straight up the only reason I got through my first-year of vet school. You're changing lives for the better guys!

Genius. A born teacher; an educator par excellence.

Really I can imagine how nice ur teachers taught u Really u r so blessed And thanks for helping many students Stay blessed

I can never thank you enough for your videos please never stop making videos you are one of the most amazing teacher on youtube

Damn... this is gold I found, gold I say!!

omg thank you so much!!! i can't believe some one caring this much to inform people .appreciate

This guy is so much dedicated to teach us and he is far away from the glamour world in which people focus on dressing well themselves he is in torn t shirt but teaching like an incomparable person🙌🙌 thank you sir 😇😇

You're explaining right from your heart, thank you so much

i will never tire of saying that you are the best teacher and this is the most amazing channel ever!!!!!!!!

I'm so in love with this channel now fr this was my first time on the channel and learnt a lot thanks blud

holy shit, talk about being able to simplify this and get the science across!!!!!! this is worth more than gold

you are a life savior. keep up the good work

Really , Sir this is amazing lecture I 'ever found thankyou Sir for wonderful explanation . Love From India May god bless you ..

Hi, i´m glad you take your time to make these videos, I really apreciate your effort . You're my inspiration. Thanks,keep doing videos please !

For sure you are a good teacher, I really appreciate you, and the way you are teaching, thank you much . May God bless you

Never met anyone this smart. Not even my lecturers can contend. No cap...thank you very much

THIS IS AMAZING THANKYOU SO MUCH FOR THE EFFORT ❤️

Thank you sm for your videos! ❤️ I don’t normally comment but seriously thankful for you making this a little easier to learn!

Amazing teaching man! It really makes it easier to understand and grasp the concepts. Love it

Hi, one correction I would like to note is that the example given in the video is spatial summation since multiple neurons were used for stimulation. Temporal summation would be used in the case of one frequently firing neuron. Other than that, thank you so much for this video, these are amazing resources!

You make medicine easy. Thank you so much!

You are SAVING my life. 🙏🏼

Great. Thanks for the informative presentation.

i am so appreciated from your teaching!

Absolutely PERFECT explanation!!! Flawless presentation! Thank you so much for making this video!

You Are A Wonderful Teacher. Thank You LEGEND ❤️❤️

WOW! I haven't met anyone who can explain science the way you explained and you are explaining from your heart and very easy to understand. Thank you!

As some other comments pointed out, there is a mistake in the explanation of summation and tetanus. The skeletal muscle AP is only a few ms long, whereas the mechanical response starts with a roughly 5-10 ms delay, and finishes around 100 ms after the AP. Therefore, the sarcolemma is already repolarized even before the contraction phase of a twitch starts! Summation, incomplete and complete tetanus happens when APs on the sarcolemma are generated in a rapid succession. Under these circumstances, calcium ions are not entirely taken back to the SR before the next "package" of calcium ions are added to the sarcoplasm. So the calcium concentration is already higher than the resting level, and with the newly released calcium, it will reach an even higher peak concentration. Depending on how quick the release events happen and for how long time, it can lead to summation (the muscle does not reach maximal tension), incomplete tetanus (maximal tension is reached at the peak of contractions, but relaxation is still visible), or complete tetanus (no relaxation between the peaks).

Ninja Nerd you are gem❤, watching from India,Your way of teaching is just awesome and every single word you explained is now fixed in my mind. Thank you so much sir.

THIS SAVED MY LIFE

OMG! It's way beyond amazing!

Thank u so much for ur effort sir u r amazing and the best teacher I have ever known .I am presently in my first year mbbs ur videos help me a lot sir.keep rocking sir...... 👍

U are the best. Well explained. Thanks for this.

Great knowledgeable video, thanks a ton!!!

This helps so much--Thank you!

This was much more understandable than my prof and books combined. 👌🏻 thank you so much!

Great explaination! God bless you

you really saved my life thanks

Eloquent and excellent

Thanks so much,,,so so informative and understandable 🙏🤍

thank you, your video help me to understand this topic, i will take the exam soon

Phenomenal lecture 👌 👏 🙌 Thank you so much ❤

where have you been all my life? THANK YOU SO MUCH

Magically wonderful

Just EXCELLENT!

this man has a natural God given talent

great detailed explanation

You are the masterpiece!!

Very helpful, thank you sir

This is so helpful omg

Very well explained sir, thank you. deserves a big like :)

Great lesson, thanks!

You are so awesome! Thank you for making this amazing videos. Better than my professors.

You are one of those spoon feeding Teachers!! Thank you much, Science got easier because of you.

Amazing! Thank you!

Thank you, you are an Amazing teacher. I aspire to be like you in future!

awesome as always, thank you

Thank you so much sir I really wish you achieve everything you ever wished for thank you sir once again

your videos blow my mind, thank you!!!!!!!!!!x100000000

Thanks for this obvious illustration

Wow, thank you so much!

Your videos are amazing !!!!!!

Thank u, thank u, thank u so much sir. Love from India. Don't know which country you belong to but you explained very nicely.

This was so helpful! I can't thank you enough!

Resting membrane potential -90mv 3:48 Threshold -55 Peak potential +30mv 10:50 Load & resistance 18:38

Actually ... U're my hero sir following u from Algeria 🇩🇿

OMG thank you for this! You are a lifesaver!!!

Thank you doc 💓

you videos helps me alot ,making studies easier...thank you

I have two questions about this: 1. If the relaxation phase takes generally longer than the contraction does, then how would one improve and shorten it for example in Wing Chun to make consecutive quick punches? 2. Can a deliberate attempt be made to achieve some level of tetanus high enough to consume enough glucose to substantially lower it and even out a spike after a meal for a insulin resistant diabetic? In my case, I have problems getting sufficient oxygen delivery from an abnormally constricted vascular system, so I have a higher ratio of white to red fiber muscles. My biggest concern now is that due to insulin use, while I am gaining muscle quickly for my age (65) I gained two inches on my arms in four months, I am also gaining fat.My waist going from 34 to 36 in the same four months. I am very upset at this fat gaining and aerobic exercise does not seem to help. I was hoping if I could burn off a lot of glucose, I wouldn't need as much insulin. Aside from breakfast, I eat four onces of carbs and four ounces of protein with plenty of fats for lunch and dinner. I spike by anywhere from 80-160 mg/dl after a meal and take 16-20 units of fast acting unsulin. Any advice is welcomeand thanks for the video.

Thank you very much.

I can’t thank you enough for the push you have given me through these tutorials. I get time to recap everything before my exams.

Beautifully explained, thank you so much.

Amazing thank you

that's amazing!!.. thank you so much ^-^

thanks so muchhhh for this video! really helped me for uni to understnand smooth and incomplete tetanus :)))

thank you. big help

Your the best. Couldn't ask for more!!!

Great source for learning..looking forward for lecture on Adaptation to anaerobic and aerobic training programs

Thank you so much, you are definitely a G.

You are awesome!

Guys believe me u need no Textbooks when u have Ninja Notes ,,,Cover almost all Guyton and Hall Love u Sir

So helpful

Amazing video, became easy to understand everything.. thanks for sharing :)

sir you told after power stroke thin filament move closure whereas in previous videos u told that iband remains constant plz explain sir.....?

Amazing 🌸✨

Wait are you said neuron number two fires in muscle fiber? OR did you mean another axon terminal branch releasing ach to increase tension? Confused because you said there is only one muscle neuron for one muscle fiber.

Wouldn't the stimulus from several different neurons be Spatial Summation and not Temporal Summation? (Top left graft)

Ur a damn good teacher bro

Dis guy is the bestest

Thank you!!!

Thank you. I should have watch your video. I wasted my whole day try to understand this stuffs.

Nice video but you may wish to review example of two distinct neurons stimulating same fiber - phyisologically any muscle fiber type can only be stimulated by one and only one motor unit that is dedicated to the target muscle from the homogenous motor neuron pool whereas one axon within the MU would deliver the action potential to its associated muscle fiber

BLESS YOU

man is carrying me through A&P